A number of techniques have been developed for eliciting high-level and predictable slips of the tongue in the laboratory. These slips appear to be involuntary, but they are complex and rule-governed, much as normal error-free speech is. Using this methodology, we have found evidence for covert anticipatory editing in speech, and for one type of "Freudian slip". In addition, certain patterns in the planning of serial actions have emerged, and the methodology for eliciting involuntary slips has in and of itself interesting implications for speech production. The present proposal suggests that this methodology can be extended straightforwardly to forms of action other than speech. Our first attempt will be to extend the results previously obtained for speech to typing of verbal and non-verbal patterns. Subsequent exploration will go in the direction on increasingly different kinds of non-speech action. In cases like typing and sign-language, our previous work can be replicated rather directly, but other purposeful actions (such as dialing a telephone or preparing a sandwich) operate over much longer time periods. It is not clear that the principles we have used previously to induce predictable slips can be extended to these cases without modification. However, a number of manipulations could be applied to increase cognitive load, so that actions with a longer time span may yet exhibit similar results. Results from this research program will: 1) make available to cognitive psychologists interested in complex action a methodology that has proved to be most fruitful in the study of speech, 2) will permit the testing of certain generalizations about the serial-order problem, 3) may make it possible to test a number of hypotheses about neglected issues in modern cognitive psychology, such as the issue of volition, and 4) may make it possible for us to understand more thoroughly than ever before a number of pathologies of action from stuttering to the expressive aphasias.